Towards Fabrication of Atomic Dopant Wires via Monolayer Doping Patterned by Resist-Free Lithography

Fabrication of atomic dopant wires at large scale is challenging.We explored the feasibility to fabricate atomic dopant wires by nano-patterning self-assembled dopant carrying molecular monolayers via a resist-free lithographic approach.The resist-free lithography is to use electron beam exposure to decompose hydrocarbon contaminants in vacuum chamber into amorphous carbon that serves as an etching mask for nanopatterning the phosphorus-bearing monolayers.Dopant wires were fabricated in silicon by patterning diethyl vinylphosphonate monolayers into lines with a width ranging from 1 μm down to 8 nm.The dopants were subsequently driven into silicon to form dopant wires by rapid thermal annealing.Electrical measurements show a linear correlation between wire width and conductance,indicating the success of the monolayer patterning process at nanoscale.The dopant wires can be potentially scaled down to atomic scale if the dopant thermal diffusion can be mitigated.     

具有调和曲率与有限$L^p$曲率的完备流形

Let(M~n, g)(n ≥ 3) be an n-dimensional complete Riemannian manifold with harmonic curvature and positive Yamabe constant. Denote by R and R?m the scalar curvature and the trace-free Riemannian curvature tensor of M, respectively. The main result of this paper states that R?m goes to zero uniformly at infinity if for p ≥ n, the L~p-norm of R?m is finite.As applications, we prove that(M~n, g) is compact if the L~p-norm of R?m is finite and R is positive, and(M~n, g) is scalar flat if(M~n, g) is a complete noncompact manifold with nonnegative scalar curvature and finite L~p-norm of R?m. We prove that(M~n, g) is isometric to a spherical space form if for p ≥n/2, the L~p-norm of R?m is sufficiently small and R is positive.In particular, we prove that(M~n, g) is isometric to a spherical space form if for p ≥ n, R is positive and the L~p-norm of R?m is pinched in [0, C), where C is an explicit positive constant depending only on n, p, R and the Yamabe constant.     

基于菌紫质F态的永久光存储研究

在线偏振飞秒激光激发下, 菌紫质通过双光子光化学反应可以生成具有永久光致各向异性的蓝移产物F₅₄₀态. 基于F₅₄₀态的永久光致各向异性, 通过调控飞秒激光空间光场分布, 可以在菌紫质薄膜中实现永久光信息存储. 本文使用纯相位型空间光调制器调制飞秒激光光场, 在物镜焦平面上生成光学点阵图案, 可以将信息快速记录在菌紫质薄膜中. 同时, 通过改变入射激光偏振方向, 可以实现偏振复用光存储, 这在高密度光存储和数据加密领域具有潜在应用.     

X箍缩三维数值模拟

利用FOI-PERFECT程序对X箍缩进行了3D数值模拟研究,给出了X箍缩的物理图像和动力学过程,探讨了Z箍缩中出现磁重联的可能性,并指出如果双丝Z箍缩中能够出现磁重联,那么X箍缩是更有利于磁重联出现的位形,并且,X箍缩中出现多重X射线暴的一个可能原因是z轴上多个位置出现磁重联。     

零气耗空气除湿实验研究

针对有热再生式压缩空气除湿装置在再生及冷吹过程中产生气耗的缺点,运用喷射器及恒压变温吸附再生原理设计了一种零气耗空气除湿工艺流程。在搭建小型实验台的基础上,通过改变喷射器引射率进行实验研究三种工况条件下活性氧化铝的吸附再生性能。实验结果表明:实验全过程能够保持一个相对稳定且有效的恒压变温吸附再生条件,且出口空气露点达到生产要求;随着喷射率的降低,吸附剂再生效果逐渐下降,而吸附效果逐渐上升。引射率为0.5时的再生时间约为引射率0.75的1.85倍,再生速率约为0.51倍。而引射率0.33,引射率0.5的吸附效率分别为引射率0.75的1.04倍,1.11倍,吸附稳定时间1.11倍,2.22倍。     

一种高稳定性光纤F-P标准具的设计

法布里-珀罗(F-P)标准具广泛应用于光纤通信与光纤传感领域。实心标准具受自身材料的限制,无法满足高稳定性的要求。空气隙标准具采用热膨胀系数极低的垫片,提高了器件的温度稳定性能。介绍了低温漂光纤F-P标准具的设计和制作,出射光自由光谱范围为100GHz,损耗为3dB,0~70℃温度漂移小于3GHz。相比于采用传统方法制作的标准具,该光纤F-P标准具稳定性更高,解决了实心标准具折射率和热膨胀变化大的问题。     

超声波辅助萃取－高效液相色谱法测定食品中碱性玫瑰精

建立超声波辅助萃取—高效液相色谱法测定含辣椒食品中非法添加剂碱性玫瑰精的方法.样品经均质,辣椒面样品、辣椒油样品、红油豆瓣酱样品分别用乙腈:水=7:3(V/V)溶液、正己烷:50％乙醇=1:2(V/V)溶液、无水乙醇经超声波辅助萃取后,用高效液相色谱仪测定碱性玫瑰精.线性范围0.026～26 μg/mL,相关系数0.9...     

杯冠衍生物BEHBCalixC6对铯离子萃取性能的研究

本文以杯冠BEHBCalixC6为萃取剂,二氯甲烷为稀释剂,通过液液萃取,研究了BEHBCalixC6对苦味酸铯的萃取性能.研究表明,随着主、客体摩尔比的增加,萃取率增大.在摩尔比50:1时,萃取率可以达到77%以上.考察了测量参比溶液、预饱和两相稀释剂、稀释剂种类和溶液中Na+浓度等因素对萃取率的影响.